title: Dissemination of resistance plasmids among gentamicin-resistant enterobacteria from hospital patients.
abstract: Out of 184 patients who were infected or colonised with gentamicin-resistant enterobacteria, 17 (9%) harboured more than one strain. Single antibiotic-resistance plasmids were common to more than one of the different organisms isolated from nine patients, strongly suggestive of in-vivo conjugation. An "epidemic" plasmid with a molecular weight of approximately 110 megadaltons was found in 11 distinct strains isolated from four patients. Seven of the organisms harbouring this plasmid were Klebsiella aerogenes. Spread of multiple-resistance plasmids among endemic gentamicin-resistant enterobacteria is not uncommon, and these organisms provide a reservoir of plasmids that may ultimately spread to more pathogenic genera.
mesh_terms: D003227:Conjugation, Genetic; D004352:Drug Resistance, Microbial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D005839:Gentamicins / Q000494:pharmacology*; D006801:Humans; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000235:genetics; D011815:R Factors
chemical_list: D005839:Gentamicins